Field of the Invention
Embodiments of the present invention relates to a piston cooling device, and particularly relates to a piston cooling device for keeping a temperature of a piston disposed in a cylinder of an internal combustion engine, at an appropriate temperature.
Background Art
Patent Literature 1 discloses a cooling device for cooling a piston disposed in a cylinder of an internal combustion engine. The piston described in Patent Literature 1 includes a cooling cavity inside the piston. The cooling cavity communicates with two inlet/outlet holes provided at a bottom surface side of the piston.
At the bottom surface side of the piston, two oil jets are provided. One of the oil jets is provided to face one of the inlet/outlet holes when the piston is located in the vicinity of a top dead center. The other oil jet is provided to face the other inlet/outlet hole when the piston is located in the vicinity of the bottom dead center.
According to the above described configuration, a flow of oil can be made in the cooling cavity by supplying oil from the one of the inlet/outlet holes when the piston is located in the vicinity of the top dead center. Further, when the piston is located in the vicinity of the bottom dead center, a flow of the oil can be formed in the cooling cavity by supplying the oil from the other inlet/outlet hole. Consequently, according to the above described conventional cooling device, the piston can be properly cooled from the inside of the piston during an operation of the internal combustion engine.